This circuit is for traditional old-style telephone lines found in an American 1980s documentation. Components are common and the optical coupler can be replaced with an equivalent.
Found in a 1967 Delco documentation, this circuit can deliver power from 40 to 50 W at 8-ohm load....
This Intersil circuit was found in a 1980s documentation. Operational are of the time, but current...
We found this circuit in a 1980s American publication from Motorola. Modern equivalent transistors...